Search

There have been many large-scale investigations of users' mobile app launch behaviour, but all have been conducted on Android, even though recent reports suggest iPhones account for a third of all smartphones in use. We report on the first large-scale analysis of app usage patterns on iPhones. We conduct a reproduction study with a cohort of over 10,000 jailbroken iPhone users, reproducing several studies previously conducted on Android devices. We find some differences, but also significant similarities: e.g. communications apps are the most used on both platforms; similar patterns are apparent of few apps being very popular but there existing a 'long tail' of many apps used by the population; users show similar patterns of 'micro-usage'; almost identical proportions of people use a unique combination of apps. Such similarities add confidence but also specificity about claims of consistency across smartphones. As well as presenting our findings, we discuss issues involved in reproducing studies across platforms.

We introduce a location--based game called Feeding Yoshi that provides an example of seamful design, in which key characteristics of its underlying technologies-the coverage and security characteristics of WiFi-are exposed as a core element of gameplay. Feeding Yoshi is also a long--term, wide--area game, being played over a week between three different cities during an initial user study. The study, drawing on participant diaries and interviews, supported by observation and analysis of system logs, reveals players' reactions to the game. We see the different ways in which they embedded play into the patterns of their daily lives, augmenting existing practices and creating new ones, and observe the impact of varying location on both the ease and feel of play. We identify potential design extensions to Feeding Yoshi and conclude that seamful design provides a route to creating engaging experiences that are well adapted to their underlying technologies.

Sharing events with others is an important part of many enjoyable experiences. While most existing co-presence systems focus on work tasks, in this paper we describe a lightweight mobile system designed for sharing leisure. This system allows city visitors to share their experiences with others both far and near, through tablet computers that share photographs, voice and location. A collaborative filtering algorithm uses historical data of previous visits to recommend photos, web pages and places to visitors, bringing together online media with the city's streets. In an extensive user trial we explored how these resources were used to collaborate around physical places. The trial demonstrates the value of technological support for sociability - enjoyable shared social interaction. Lastly, the paper discusses support for collaborative photography, and the role history can play to integrate online media with physical places.

Social Proximity Applications (SPAs) are a promising new area for ubicomp software that exploits the everyday changes in the proximity of mobile users. While a number of applications facilitate simple file sharing between co–present users, this paper explores opportunities for recommending and sharing software between users. We describe an architecture that allows the recommendation of new system components from systems with similar histories of use. Software components and usage histories are exchanged between mobile users who are in proximity with each other. We apply this architecture in a mobile strategy game in which players adapt and upgrade their game using components from other players, progressing through the game through sharing tools and history. More broadly, we discuss the general application of this technique as well as the security and privacy challenges to such an approach.

Outdoor multi-player games are an increasingly popular application area for ubiquitous computing, supporting experimentation both with new technologies and new user experiences. This paper presents an outdoor ubicomp game that exploits the gaps or seams that exist in complex computer systems. Treasure is designed so that players move in and out of areas of wireless network coverage, taking advantage not only of the connectivity within a wireless ‘hotspot’ but of the lack of connectivity outside it. More broadly, this paper discusses how the notion of seamful design can be a source of design ideas for ubicomp games.

This paper presents Treasure, an outdoor mobile multiplayer game inspired by Weiser's notion of seams, gaps and breaks in different media. Playing Treasure involves movement in and out of a wi-fi network, using PDAs to pick up virtual 'coins' that may be scattered outside network coverage. Coins have to be uploaded to a server to gain game points, and players can collaborate with teammates to double the points given for an upload. Players can also steal coins from opponents. As they move around, players' PDAs sample network signal strength and update coverage maps. Reporting on a study of players taking part in multiple games, we discuss how their tactics and strategies developed as their experience grew with successive games. We suggest that meaningful play arises in just this way, and that repeated play is vital when evaluating such games.

Mobile and wearable computers present input/output prob-lems due to limited screen space and interaction techniques. When mobile, users typically focus their visual attention on navigating their environment - making visually demanding interface designs hard to operate. This paper presents two multimodal interaction techniques designed to overcome these problems and allow truly mobile, 'eyes-free' device use. The first is a 3D audio radial pie menu that uses head gestures for selecting items. An evaluation of a range of different audio designs showed that egocentric sounds re-duced task completion time, perceived annoyance, and al-lowed users to walk closer to their preferred walking speed. The second is a sonically enhanced 2D gesture recognition system for use on a belt-mounted PDA. An evaluation of the system with and without audio feedback showed users' ges-tures were more accurate when dynamically guided by au-dio-feedback. These novel interaction techniques demon-strate effective alternatives to visual-centric interface de-signs on mobile devices.